Hi

I have a 2010 octavia 1.6 tdi estate with 93000 miles on it. I have had it for 18 months and 13000 miles.

For most of that time the engine management led has been lit. My garage has replaced both of the sensors which may be causing this and assured me the tube is clear.

The car regularly returns 55-58mpg at fill-ups and runs very well, but the led is annoying.

I purchased a copy of the ross-tech diagnostic software. The error is 'implausible signal' but nobody will tell me what it means or how to fix it.

I clear the faults with the software but it's back in one to two days.

I produced a print out and gave it to the local Skoda dealer but they were no use at all! Refused to look at it and wanted me to pay £100 to run their software which I am sure would give exactly the same report and then probably tell me I should spend £1000s on unnecessary repairs.

I have looked carefully at the values in the dpf section which Ross-tech software reported. I can confirm that the regen does happen, there is very little soot in the system and about 42g of ash. I understand that the amount of ash is typical of the mileage and nothing to worry about.

I have been using both Wynn's and Redex diesel fuel additive to clean the system but this has no effect.

Implausible signal means the sensor is giving a stupid reading. Say if it was a temperature sensor saying it's -70 degrees outside when it obviously isn't.

Suggests a problem with the sensor rather than the wiring.

Sent from my D5803 using Tapatalk

What fault is it? An autoscan would help...

This is the engine report.

As I mentioned, I understand there are two sensors, I have been assured both were replaced.

 

Address 01: Engine (J623-CAYC)       Labels: 03L-906-023-CAY.clb
   Part No SW: 03L 906 023 AG    HW: 03L 906 023 AG
   Component: 1,6l R4 CR td H23 5697  
   Revision: --------    Serial number:               
   Coding: 00114016032500080000
   Shop #: WSC 73430 031 00999
   ASAM Dataset: EV_ECM16TDI02103L906023AG 001003
   ROD: EV_ECM16TDI02103L906023A_VW32.rod
   VCID: 6BCDD057D38509DADA52491-803E

2 Faults Found:
7347 - Diesel Particle Filter; Differential Pressure Sensor
          P2453 00 [237] - Implausible Signal
          MIL ON - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 254
                    Mileage: 147473 km
                    Date: 2016.03.26
                    Time: 19:19:59

7346 - Diesel Particle Filter; Differential Pressure Sensor
          P2453 00 [237] - Implausible Signal
          MIL ON - Confirmed - Tested Since Memory Clear
             Freeze Frame:
                    Fault Status: 00000001
                    Fault Priority: 2
                    Fault Frequency: 1
                    Mileage: 147473 km
                    Date: 2016.03.26
                    Time: 19:23:41

Readiness: 0000 0000

When we're the sensors replaced? Who did it and where they correctly adapted when installed?

Also the ash content on the CR engines is measured in ml not g IIRC.

Sent from my D5803 using Tapatalk

There is only one pressure sensor.

Three temp sensors and an oxygen sensor.

Edited 13 June, 20169 yr by Tech1e

Thanks for the advice.I'll go back to the garage that fitted the replacement sensors and ask them to look again.

Peter

If they didn't calibrate it it's a waste of time replacing it.

However there are quite a few software updates to go with sensors (or at least were) so if your not visiting a main dealer you may well not be getting the repair you need.